The 38-year old was simply inspired as he kept his side in a one-sided match that had threatened to turn into a goal feast for the home supporters.
But after Aaron Downes had headed Chesterfield into an early lead, they failed to kill Dagenham off and Paul Benson earned his side a draw with a 56th minute breakaway goal.
But without Roberts, Dagenham would have been on the end of a real hiding. The ex-Welsh International made save after save as Chesterfield ripped the visitors' defence to pieces in the first half.
The trickery of Jack Lester and the midfield pairing of Derek Niven and Peter Leven was too much for the League newcomers who at times were chasing shadows.
But the second goal would not come although Lester should have grabbed his 10th of the season in the 34th minute when he took the ball round Roberts but waited too long and the keeper got back to block his shot.
Roberts made two more outstanding saves before Chesterfield's defence was caught cold by a quick break that allowed Benson to take the ball past Barry Roche and squeeze in a low shot from a tight angle.
But even then Chesterfield looked capable of scoring again but Roberts denied Lester two minutes later and then the former Nottingham Forest striker lost control when Leven set him up with a defence-splitting pass.
Benson could have given Dagenham the lead six minutes from time when he was sent clear but this time Roche made a crucial save and it was left to Roberts to perform more heroics in the closing minutes.
Substitute Wayne Allison saw a low shot brilliantly turned away by Roberts and then in stoppage time Phil Picken unleashed a drive from the edge of the area that was heading for the top corner until Roberts leapt to claw the ball to safety.